BC researchers develop material sterilization methods using visible light

Research shows the potential of reducing the environmental impact and shortages of single-use PPE

Blue disposable masks stacked on top of each other
Sterilization technology can relieve stress from lack of PPE equipment in rural communities and lessen environmental impacts of single use plastic. PHOTO: Jievani Weerasinghe / Unsplash

By: Yelin Gemma Lee, News Writer

Researchers from SFU and the University of Victoria (UVIC) have developed a method to sterilize non-woven polypropylene materials using visible light. These materials are commonly found filtering personal protective equipment (PPE) used largely in healthcare settings such as single-use medical masks and respirators. 

The Peak spoke to Tyler Cuthbert, who led this study when he was a post-doctoral fellow at SFU school of engineering science. 

“We were able to take something called a photosensitizer, which can convert visible light into [a molecule] called reactive oxygen species, and we were able to put this specific molecule and attach it onto polymers and materials that are commonly used in healthcare,” said Cuthbert. By inserting a light-sensitive compound developed by UVIC chemistry professor Jeremy Wulff, viruses attached to polypropylene fabric were 99.9% inactivated after four hours under intense visible light.

A polymer is a molecule made up of a series of building blocks connected by bonds. A polymer can be artificially made, such as nylon or plastics, or naturally available, such as cotton or wool. 

Cuthbert explained Wulff’s research group and their chemical insertion method is “typically a difficult process to do from a chemistry standpoint.

“It’s a method that can functionalize relatively any polymeric material that has CH bonds, and that’s pretty much all of them,” said Cuthbert. “The applicability of this to a large variety of materials or products or devices is quite widespread [ . . . ] the potential is there to be able to incorporate these types of advanced materials into lots of different products for potential commercialization in the future.”

Cuthbert explained there are many opportunities for this research to be used in the future to lessen the impacts of viruses on the healthcare industry and supply shortages. 

“The advantage of this kind of technology, looking forward, is that there’s a potential it can eliminate some of the problems with the current subset of PPE infiltration technology which is really just single use,” said Cuthbert. “These materials could be reused after they undergo some exposure to light and the light we’re talking about is visible light so it’s very accessible.” 

Cuthbert said even sunlight could work, although depending on the strength of the light the time it takes to sterilize the fabric would differ. He said this could enable remote communities with limited supplies available to extend the life cycles of PPE rather than having to throw it away or have it go through a harsher sterilization processes.

He added this research could also be used in the future to lessen the massive environmental impact of single-use polymers and plastics. He hopes single-use products such as masks can be resterilized and reused, or recycled and given a new lifecycle.

“Putting advanced technology or advanced material science into some of these commodity products could have benefits far-reaching just the impact of the user but more the environment and how we see the future of the devices that we use to protect ourselves,” said Cuthbert.

This collaborative study is published and accessible online for free on Scientific Reports.